Device for use with telautographs.



PATBNTED JULY 19 F RITCHIE DEVICE FOR USE WITH TELAUTOGRAPHS.

APPLICATION FILED JAN 3 1902 N0 MODEL.

I U TED STATES Patented Jieiy l9, I904 PATENT OFFICE.

I '1 DEVICE: FOR USE WITH TELAUTOGRAPHS.

I SPECIFICATION forming part of Letters Patent No. 765,441, dated July 19, 1904. Application filed January 3,1902. Serial No. 88,356. (No model.)

i To rill whom it may concern:

it known that I, Fos'rER RITCHIE, a citizen of .the United States of America, residing at MackesonroadHampstead, in the county of London,;England, have invented certain new and useful Devices for Use with Telautographs, (for which I have applied for a patgent in GreatBritain, dated December 13, 1901,

,No.25,496,,) of which the following is a speci- I apparatus for adjusting and indicating the re-l sistance in the line-wires of telautograph sys- 15 term, so that a subscriber can see at a glance Thisinvention relates to telautograph's.

The ob ect of the invention is to provide an if the resistance of the line-wires is in proper condition and to bring it into proper condition if it. is not so.

- i further object of the invention is to providean; indicator for informing a subscriber whether or not his communication is'cut off 'at the exchange or elsewhere through accident or otherwise.

- appearing thereon, Figure 1 is a view in plan,

showing an ordinary galvanometer employed in connection with an indicator apparatus embodying my invention. Fig. 2 is a view in plan of two rheostats employed in connection with my invention. Fig. 3 is a view in vertical central section of the rheostats and galvanometer embodying in their relative arrangement and location the principles of my invention. p

In telautograph apparatus and systems such as is described in Patent No. 610,274, dated September 6, 1898, to'Leon McPherson, it is necessary to maintain the resistance of the external line-wires substantially constant in order to secure the best results. I

In the case of lines of various lengths radiating from an exchange it may often occur .that the resistance of the external circuit is less than that for which the apparatus is dequired to be introduced in order to bring the total resistance up to that for which the apparatus is sought. It may also sometimes occur that a subscriber is out OK accidentally'or.

otherwise by the exchange operator before his communication is finished without the sender knowing that his communication has been interrupted, and in such case the sender will continue writing messages which are not received or recorded at the receiving-station. It is the special purpose of the present invention to avoid these objections and to provide an apparatus which will indicate to the sender whether or not the resistance condition of the line-wires over which he is operating is in proper ad ustment and whether or not his line of communication has been lnterrupted or out 0a through accident or otherwise.

In accordance with my invention I employ two rheostats, (indicated on the drawings at d and 0,) preferably arranged in arcs of a circle'concentric with the pivot of a lever 00, said lever provided with brushes 6 0, respectively, operating over the rheostat-segme'nts d and e, and the lever a is provided with an operatinghandle One terminal of the telautographbattery is connected electrically with the lever aas, for instance, at the point of its piv otal support, as shown at wfrom which point the current will divide, part passing from one arm of said lever and brush 6 and the coils of the rheostat d, terminal (see Fig. 2,) and out to return through the left-hand rheostat of the telautograph apparatus. (Not shown.) The other part of the current passes through the other arm of lever a, through contactbrush a, the coils of resistance or rheostat 6, wire 2, and out to line through the right-hand rheostat of the telautograph apparatus. (Not shown.) In one of these line connections from the rheostats (Z eas, for instance,'in

the form shown,=but to which my invention is not to be limited-in the wire extending from the rheostat d I place a signal device such, for instance, as a galvanometerthe coil f of which is included in this line-circuit.

It is obvious that the rheostat may be included in the circuit from rheostat e, if desired. Only one rheostat is ordinarily necessary, because the two circuits are generally under c'ondiv tions so nearly equal that the same resistance the telautograph, the signal device will indicate the fact. For instance, in the form illustrated, to which the invention is not limited, the index of the galvanometer will be deflected to the one side or the other of the middle point it of the dial in connection with which said index operates. The operator then moves the lever on and its brushes 7) c by means of the handle in in one direction or the other to introduce or cutout resistance of the rheostats (Z 0 until the signal device again indicates proper resistance condition in the linecircuits-as, for instance, to bring the galvanometer-index to middle positionthe proper adjustment of the external circuit in respect of resistance being thus effected. It is convenient to arrange the galvanometer and. its connections in case a galvanometer is employed as the signal device'in such a way that the index thereof moves in the same direction as the handle :76, so that the-operator seeing that a .i index has to move to the right 40 or to the left in order to be brought to its middle or neutral point moves the handle to the right or left accordingly. It will also be obvious that in case the operator or sender should have his communication cutoff while he is transmitting or sending the fact will be at once indicated by the signal device-as, for instance, by variations of the position of the galvanome'ter-index.

' Having now set forth the object and nature of my invention and a construction embodying the principles thereof, what I claim as new and useful and of my own invention, and desire to secure by Letters Patent, is

An instrument adapted to be used with a telautograph apparatus for adjusting and indicating the resistance of the external circuits, comprising a frame having two series of contacts with interposed resistances, a

swinging arm having spring-brushes to slide upon said contacts, and in electrical connection with one another, and terminals upon the instrument connected respectively tosaid arm and the end contacts of said series, the said terminals being connected to add corresponding resistances in each series upon movement of the arm, and a current-indicator device mounted upon the instrument and in series with one of said circuits, as and for the purpose set forth.

In testimony whereof I have hereunto set my hand in presence of two subscribing witnesses.

FOSTER RITCHIE.

Witnesses;

W. J. NoRwooD, Josnrn LAKE. 

